The fuel cell described in Japanese Patent Application Publication JP 2003-077499 A is provided with a membrane-electrode-assembly (MEA) in which an electrolyte film is sandwiched between a fuel electrode and an air electrode, a resin frame surrounds the periphery of the MEA, and a pair of separators sandwich both the MEA and the resin frame. Both the fuel electrode and the air electrode are provided with a gas diffusion layer on their outside.
In addition, in the fuel cell, between the resin frame and both separators are provided a manifold portion and a flow rectifier or distribution portion, respectively. Moreover, projections are provided on both sides of the resin frame to hold the necessary gas flow height by contacting each separator. Thus, the fuel cell circulates reactant gas (fuel gas and oxidant gas) through the membrane-electrode-assembly. The separator is also used for a current collector and external terminal in addition to functioning as a gas seal for the reactant gas.
The above fuel cell is configured to make up a fuel cell stack by stacking multiple sheets. When configuring this fuel cell stack, pressure is exerted in the stacking direction in order to maintain good assembly accuracy, gas seal property and electrical conductivity.